▎ 摘　　要

NOVELTY - A coating composition comprises 1-45 wt.% modified filler and 55-99 wt.% performance modifier. The modified filler comprises 15-98 wt.% heavy calcium carbonate, 1-30 wt.% fine ceramics, 0.1-20 wt.% beryllium oxide, 0.1-20 wt.% boron nitride, 0.01-15 wt.% chromium oxide, 0.01-10 wt.% carbon fiber ash and 0.001-5 wt.% graphene. The performance modifier comprises 40-99 wt.% 40-99 wt.% high-solid content epoxy compound, 0.1-30 wt.% % styrene-methacrylate-butadiene copolymer, 0.1-25 wt.% fluorinated polyester, 0.01-15 wt.% methyl cyanoacrylate, 0.01-10 wt.% polybenzimidazole, 0.01-10 wt.% propylene glycol alginate, 0.01-10 wt.% octadecyltriethoxysilane and 0.01-10 wt.% stearyl alcohol. USE - Composition is used in protective coating of steel structure (claimed) used in road facility, bridge and deck plate. ADVANTAGE - The composition has excellent adhesiveness with respect to the steel structure so that the occurrence of cracks on the coated surface and peeling of composition from the base surface can be suppressed, reduces maintenance cost of the steel structure, and suppresses deterioration of the steel structure due to UV rays, thus enhancing its durability. The steel structure has high tensile strength and elongation rate, and excellent corrosion resistance, and resistance to bending and impact. By using the laser beam surface treatment apparatus, the generation of dust and foreign substance is completely removed, thereby preventing environmental pollution. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for protective coating of steel structure, which involves removing rust and foreign substances from a steel structure using a laser beam surface treatment apparatus, coating with a putty material and treating the ground surface so as to be flat, forming a primer layer on the treated steel structure, applying and curing the coating composition on the primer layer, and applying the surface protective/reinforcing coating composition.